Extended-life cement compositions are provided and, more particularly, extended-life cement compositions are provided that comprise a cementitious component comprising red mud solids and hydraulic cement.
Cement compositions may be used in a variety of subterranean operations. For example, in subterranean well construction, a pipe string (e.g., casing, liners, expandable tubulars, etc.) may be run into a wellbore and cemented in place. The process of cementing the pipe string in place is commonly referred to as “primary cementing.” In a typical primary cementing method, a cement composition may be pumped into an annulus between the walls of the wellbore and the exterior surface of the pipe string disposed therein. The cement composition may set in the annular space, thereby forming an annular sheath of hardened, substantially impermeable cement (i.e. a cement sheath) that may support and position the pipe string in the wellbore and may bond the exterior surface of the pipe string to the subterranean formation. Among other things, the cement sheath surrounding the pipe string prevents the migration of fluids in the annulus and protects the pipe string from corrosion. Cement compositions may also be used in remedial cementing methods to seal cracks or holes in pipe strings or cement sheaths, to seal highly permeable formation zones or fractures, or to place a cement plug and the like.
A broad variety of cement compositions have been used in subterranean cementing operations. In some instances, extended-life cement compositions have been used. In contrast to conventional cement compositions that set and hard upon preparation, extended-life cement compositions are characterized by being capable of remaining in a pumpable fluid state for at least about one day (e.g., about 7 days, about 2 weeks, about 2 years or more) at room temperature (e.g., about 80° F.) in storage. When desired for use, the extended-life cement compositions should be capable of activation and consequently develop reasonable compressive strengths. For example, an extended-life cement composition that is activated may set into a hardened mass. Among other things, extended-life cement compositions may be suitable for use in wellbore applications such as applications where it is desirable to prepare the cement composition in advance. This may allow the cement composition to be stored prior to use. In addition, this may allow the cement composition to be prepared at a convenient location before transportation to the job site. Accordingly, capital expenditures may be reduced due to a reduction in the need for on-site bulk storage and mixing equipment. This may be particularly useful for offshore cementing operations where space onboard the vessels may be limited.
While extended-life cement compositions have been developed heretofore, challenges exist with their successful use in subterranean cementing operations. For example, some extended-life compositions may have limited use at lower temperatures as they may not develop sufficient compressive strength when used in subterranean formations having lower bottom hole static temperatures. In addition, it may be problematic to activate some extended-life cement compositions while maintaining acceptable thickening times and compressive strength development. Moreover, supply/inventor constraints may restrict the availability of certain key components of extended-life cement compositions depending on geographic availability.